Run-down and reset locomotive-control apparatus



M. E. MILLER April 15, 1930.

RUN-DOWN AND RESET LOCOMOTIVE CONTROL APPARATUS Original Filed Jan. 15

Patented Apr. 15, 1930 Uhli'thfi S'tA'liEd @ATENT OFFME MONROE E. MILLER, OF VVASI-IENGTON, DISTRICT OF COLU'JD'IBIA, ASSIGNOR, BY MESNE ASSIGNMENTSJTO UNION SIMPLEX TRAIN CONTROL (10., INC., A CORPORATION OF DELAWARE RUN-DOWN AND RESET LOGO'MOTIVE-CONTROL APPARATUS Original application filed January 15, 1923, Serial No. 612,780. Divided and this application filed July 11,

The present invention relates to automatic apparatus for controlling the movement 01" locomotives, street cars or other self-propelled vehicles that travel along tracks, and is more it particularly an improvement in the run-down and reset type of control, wherein means are providedior retarding or stopping the locomotive when it has travelled a predetermined distance unless such means are reset at designated intervals, thereby requiring impulses 539 in a block, and then permitted to proceed,

with or without speed control, if trailic conditions permit, without waiting until the end of the block is reached for a clear or proceed indication, to facilitate traiiic and avoid coir gestion by unduly retarded movements. The

present apparatus is a compromise between what is known as intermittent or block entrance initiated control and continuous control, having advantages of both and eliminating certain disadvantages of each of them.

Another ob eet of the invent1on is the provision of a run-down and reset locomotive control apparatus enabling several difierent conditions to be obtained while the locomotive is moving along the track, either in a block or from one block to another, such as the establishment ofa caution condition and restricted speed control, in addition to a danger or locomotive stopping condition.

Another object is the provision of such an apparatus which enables a clear or free running condition to be obtained while proceeding under speed restriction, and while travelling in a block, so that if the locomotire is travelling under danger speed control a caution speed control condition can be established, and if the locomotive is proceed- 59 ing under either danger or caution speed con- Serial No. 204,985.

novel means for controlling the circuits of the electrical control elements of the track dependent on tratlic conditions; a further ob ject being the obtainment of different conditions of the control elements when there are vehicles on the track different distances ahead, such as one condition when the track is clear, that is, when a certain number of blocks ahead are unoccupied, a caution condition when a certain block ahead is occupied and a danger condition when the next block ahead is occupied; and a still further object, in this connection, is to so arrangethe circuits of the control elements of the track that electrical current is not used for such elements unless a vehicle is travelling in a block, and then the control elements of such block only use electrical energy, providing clear or caution conditions exist.

It is also an object of the invention to improve this type of apparatus generally as well as in its details, to provide a practical and operative organization of correlated. ele ments and devices, and to adequately supply the needs and requirements for automatic locomotive or train control without the obj ections incident to continuous and blockentrance initiated control apparati as heretofore proposed.

it the foregoing and other objects in view, which will be apparent as the description proceeds, the invention resides in the construction and combination of parts, as hereinafter described and claimed, it being understood that changes can be made Within the scope of what is claimed, without departing from the spirit of the invention.

The invention is illustrated in the accomanying drawing, wherein the apparatus is illustrated diagrammatically.

Normal running circuit An electro-magnet controls an air valve or other device, so that when said magnet is deenergized the brakes are applied, the steam, electrical or other power shut off,v or both, so that such magnet must be kept energized in order that the locomotive may proceed. The locomotive-stopping magnet 10 is therefore disposed in a normal running circuit including the generator 11 or other source of electrical energy, magnet 10, switch 12, contact 13, clear-maintaining electro-magnet 14 normally holding the switch 12 against the contact 13, conductor 15, blade 92 of a reversing switch, contacts 16" bridged by the armature 54", another blade 94 of the reversing switch, conductor 95, returning to the generator through the helix 28 and lever 24, switch 17, contact strip 18, conductor 19, switch 21, contact strip and conductor 22. With this circuit closed the magnet 10 is energized so that the locomotive can proceed, and the clear maintaining magnet 14 is energized to hold the switch 12 against the contact 13, which is necessary if the train is to proceed without speed restriction, the magnet 14 when deenergized enforcing the speed control, as will hereinafter more fully appear. V

Run-down device The switch 17 is operated by a run-down device that will remove the switch 17 from the strip 18 unless the device is reset. This run-down device, designated generally at 23, in the embodiment as shown, comprises a pivotally mounted lever 24 to which the switch 17 is secured, and the lever 21 has a weight 25 so that the lever will gravitate when free to do so. A rod 26 is slidable through a guide 27 with which the lever is provided, and projects beyond the end of the lever to enga e a helix 28, which, as shown, is concave or curved lengthwise about the pivot of the lever as a center, in order that the terminal of the rod 26 may follow the helix in the downward swinging movement of the lever. The helix has an annular flange or landing 29 at its lower end, on which the rod 26 can come to rest when the rod has followed the helix down to the lower end thereof, there by permitting the helix to continue revolving while the lever 24 remains in its lowermost position The helix 28 is driven from a wheel 30 of the locomotive or other driving member which rotates in proportion to the speed and distance of travel of the locomotive, and any suitable reversing gear 31 is located between the wheel 30 and helix 28,

so that said helix will rotate in the same direction when the locomotive travels in either direction, this being essential in order that the helix will travel in the same direction even though the locomotive may be turned around with either end foremost Thus, the projecting end of the rod 26 bearing on the helix 28 will follow said helix down, as the helix rotates, whereby the lever 24 moves downwardly in proportion to the distance of travel of the vehicle, and the lever will move on down to its lowermost position unless reset.

The centrifugal speed governor 32 is geared, as at 33, to the helix 28, so that the governor is driven from the helix which retards the movement of the lever or member 24, and this assures that the helix or member 28 must be rotating if the governor is in op eration. The switch or brusn 21 is carried by the governor, being insulated therefrom, a

the magnet 10 and stop the locomotive should a the governor fail to operate while the locomotive is running. The ap between the strip 20 and switch 21 can be bridged, however, when an intentional stop is made by the engineer or motorman. Thus, the throttle lever or power control member 34 can be used to bridge such gap when said member is moved to shut off the power. As shown, the conductor 22 is connected to the lever or member 34, and a contact 35 is connected to the 1. 5:?

switch or brush 21, so that the lever 31 in being moved to initial position to shut oil the power, will. engage the contact 35, thereby forming a. bridge between the strip 20 and switch 21. between the conductors 19 and 22 While the power is shut off. Therefore, when an intentional stop is made, even though the switch 21 moves away from the strip 20, the circuit of the magnet 10 is not opened at this point, but the circuit will be opened if the member 34 is advanced to remove it from the contact 35 and the governor 32 is not rotating sutiiciently to raise the switch 21 against the The strip 20 is sufficiently f This will keep the circuit closed 1.7.

strip 20. hen the locomotive is started, the all:

member 34 remains in engagement with the contact 35 for a sufficient interval to enable the governor to raise the switch 21 against the strip 20 before the member 31- is removed from the contact 35, but, when the power is applied fully and the member 3 1 removed from the contact 35, should the governor 32 fail to operate, the switch 21 not being returned to the strip 20, will open the circuit r; ting of the run-down device occurring.

Resetting device The lever 24 of the run-down device must be reset or raised before the switch 17 is removed from the strips 16 and 18, or speed restriction or stopping of the locomotive will be enforced by the mere travelling of the comotive a given distance without the reset- In this way, the run-down device is operable to produce an ultimate caution or danger condition, unless the run-down device is reset or restored at intervals. The run-down de- 1 vice thus controls the circuit of the magnet 10 to produce a locomotive retarding or stop ping condition, without any responsive control between the vehicle and track, should the locomotive proceed without proper impulses .or indications being received from the track that control the resetting device.

In the embodiment as shown, the resetting device comprises a solenoid or eleotro-magnet 36 having the core or armature 37 to be raised when the solenoid is energized, and

said core is connected by a link 38 with a lever 39 fulcrumed to the lever 24. The link 38 is connected to one arm of the lever 39 and the other arm of said lever 39 is pivoted to the rod 26, so that when the core 37 is raised, the lever 39 is swung to retract the rod 26 from the helix 28. The lever 24 has stops to limit the movement of the lever 39 and rod 26 with reference to the lever 24, and a suitable spring 41 is provided to yieldingly project the rod 26 from the lever 24 to en gage the helix. Should the rod 26 be broken off or should the spring fail to project the rod, the lever 24 can gravitate at once,

' as soon as the solenoid 36 is deenergized, to

produce a danger condition, so that the presence of the rod 26 and helix 28 is necessary to support the lever 24 for downward move ment in proportion to the distance of travel of the locomotive. When the solenoid 36 is deenergized, the weight of the core 37 is imposed on the lever 24 to assist in moving the lever downwardly. VVhenthe lever isin any position and the solenoid 36 is energized, the core 37 being raised will first swing the 'lever 39 to retract the rod 26 from the helix 28, the spring 41 having only a slight tension, and the lever 24 is then raised back to its initial or starting position Caution speed control circuit The contact strip 18 is sufiicient'ly short so that when the lever 24 of the run-down device moves to its run down position, the switch 17 is removed from the-strip 18, there by opening the circuit through the clear maintaining magnet 14, so that the switch 12 drops and enforces a speed restriction or stopping of the vehicle. Supposing the lever 24 to have moved downwardly sufficiently to remove the switch 17 from the strip 18, there will be established a danger condition, by the deenergization of the magnet 10, but supposing the rundown device to be reset, with the switch 12 bearing against the contact 42, there will he established a caution speed control circuit including the generator 11, magnet 10, switch 12, contact 42, conductor 43, caution speed control contact strip 44, switch carried by the governor 32, metallic conductive connection of the switch 45 to the helix 28, rod 26, lever 24, switch 17, contact strip 18, conductor 19, strip 21, contact strip 20, and conductor 22 The strip 18 and switch 21 remain in the circuit of the magnet 10 when such caution speed control circuit is established. The switch 45 may be grounded directly to the lever 24, but, in grounding the switch 45 to the helix 28, the current must flow from the helix through the rod 26, so that if said rod fails to contact with the helix, due to a fault in the mechanism, the circuit will be opened. The switch or brush 45 is raised and lowered by the governor, depending on the speed, and the strip 44 is of such length as to only be engaged by the switch 45 when the locomotive is travelling below a predeter mined speed, say fifteen miles per hour, so that if such speed is exceeded with the switch 12 down, the circuit will he opened between the strip 44 and switch 45, to ,deenergize the magnet 10 and retard the locomotive until the speed is reduced for the return of the switch 45 to the strip 44. Thus, the moment the switch 12 is released from the magnet 14 with the lever 24 raised the speed restriction for caution conditions will be established, requiring the locomotive to travel below the maximum speed for such condition. A caution condition in the vehicle equipment is thus established-when the run-down device has run down part way and is reset, butthe switch 54" is opened as will appear more fully hereinafter. The strip 18,and switch 21 and strip 20 are still in the circuit of the magnet 10, however, to break such circuit if the governor should stop or if the switch 17 is removed from the'strip 18 by the further downward movement of the lever 24, the breaking of said circuit resulting in a danger condition.

Danger speed control circuit lVhen the lever 24 moves downwardly to carry the switch 17 away from the switch 18,

danger conditions are established in the vehicle equipment and a danger speec control circuit is established including the generator 11, magnet 10, switch 12, contact 42, conductor 43, caution speed control strip 44, switch 45, contact 46 engaged by the switch when the governor has stopped, contact 47, normally gravitated switch 48, electroanagnet 49, conductor 50, switch 51, conductor 19, switch 21, strip 20 and conductor 22. However, it the locomotive is in motion and the switch 45 is raised from the contact 46, said switch only engaging the contact when the governor has stopped, such circuit will remain open to require the stopping of the locomotive because of the magnet 10 being deenergized. Now, when the locomotive has been brought to a stop so that the switch 45 engages the contact 46, and the engineer or motorman closes the switch 51, such circuit will be established to energize the magnet 10 again whereby the locomotive can proceed, providing, under this danger condition, the engineer holds the switch 51 closed, thereby requiring him to be alert. Such circuit being closed will energize the magnet 49 and raise the switch 48 from the contact 47 into engagement with a contact 53, which is connected to a danger speed control contact strip 52 engaged by the switch 45 when the locomotive is travelling at a predetermined slow speed, say five or eight miles an hour or less. The strip 52 is sufiiciently short so that the switch 45 will be removed therefrom as soon as such restricted danger speed is exceeded. The change of connection from the contact 46 to the danger speed control strip 52 is necessary to enable the locomotive to proceed, inasmuch as the switch 45 is raised from the contact 46 as soon as the vehicle moves. The circuit from the strip 44 to the conductor now includes the contact strip 44, switch 45, contact strip 52, contact 53, switch 48 and magnet 49 holding the switch 48 raised. This enables the locomotive to proceed but if the restricted speed is exceeded, the switch 45 being removed from the strip 52, will open the circuit and deenergize the magnet 10. The magnet 49 will also be deenergized, letting the switch 48 drop into connection with the contacts 47 and 46, and the locomotive must again be brought to a stop before it can proceed further. A stop of the locomotive is therefore enforced whenever the maximum speed under danger conditions is exceeded, before the locon iotive can move on. Also, the engineer must hold the switch 51 closed, so as to be alert, to proceed under danger speed control, and if he releases the switch 51, the circuit is opened and the locomotive stopped. This requires the alertness of the engineer while under danger control.

When the caution s eed control circuit is established, as herein efore described, the contact 13, magnet 14, conductor 15, reversing switch blades 92, 94, contacts 16", switch 54 and conductor 95 are replaced by the contact 42, conductor 43, strip 44, switch 45 and the metallic connections to the lever 24, and when the danger speed control circuit is established, the switch 17 being removed from the strip 18, the contact 13, magnet 14, conductor 15, switch blades 92, 94, contacts 16", switch. 54 and conductor 95, together with the lever 24, switch 17 and strip 18, are replaced by the contact- 42, conductor 43, strip 44, switch 45, contact 46 or strip 52, switch 48, conductor 50 and switch 51, the clear, caution and danger circuits all leading through the conductor 19, switch 21, strip 20 and conductor 22 back to the generator 11.

Resetting circuits The energization of the solenoid or magnet 36 for resetting the run-down devices is controlled by suitable responsive elements or devices carried by the locomotive or vehicle. In the embodii'nent as shown such responsive elements comprise armatures or switches 54 and 54 or other members magnetically responsive to magnetic fields created on the track, although the impulses or indications from the track to the locomotive can be obtained in any of the well known manners, there being different kinds of control and responsive elements available for accomplishing the same results. The armatures or switches 54 and 54" are carried by weighted levers or switches 55 and 55", respectively, and when the armatures are attracted to magnets on the track, the switches 55 and 55" are moved against the respective contacts 56 and 56". This response of the responsive elements or armatures is used for energizing the solenoid 36 to reset the rundown device, and means is provided whereby the solenoid 36 can be energized for a sufiiciently long interval to completely raise the lever 24, although, with a fastmoving locomotive, the armature 54 or 54" may pass the track magnet in a very small fraction of a second, the raising of the lever 24, however, requiring but a very short interval f time so that the lever is returned quickly before the locomotive has moved more than a comparatively short distance. An electromagnet 57 is used for changing circuit connections, and when the switch 55 or 55" engages its contact 56 or 56", a circuit is closed including the generator 11, magnet 57, switch 58 normally dropped onthe contact 59, conductor 60,blade 96 of the reversing switch contact 56", switch 55", conductor 61, a contact strip 62, a bridging switch 63 carried by and insulated from the switch 17, a companion contact strip 64, and a conductor 65. If the switch 55 is closed instead of the switch 55", the circuit between the contact 59 and conductor 61 includes the conductor 97, electro-magnet 103, conductor 98,

blade 99 of the reversing switch, contact 56' and switch The lever 24 being down part way will cause the switch 68 to bridge the contact strips 62 and 64, and the magnet 57 being energized, by the closing of the switch even though for a slight instant, will pick up the switch 58 and remove it from the contact 59 to raise the switch against a contact 6'? in toe circuit of the solenoid 86. This closes the circuit oi the solenoid 86 including the generat r 11, magnet 57, switch 58 held in raised position by the magnet, contact 67, conductor (it, solenoid 36, conductor 61, contact strip 62, switch 68, e011- tuct strip 64 and conductor 65. The response of the armature 54. or 54: will therefore first energize the-magnet 57 to raise the switch 58 against the contact- '67, which will close the circuit of the solenoid 86 and such circuit will remain closed until the lever 24: is returned to its starting position, at which time the switch 63 being removed from the strips 62 and 64: will open the circuit. The solenoid 86 then becomes deenergized and the magnet 57 also becomes deencrgized to release the switch 58, thereby breaking the circuit at two points, and the lever 24- will be released to immediately start'downward again. By this arrangement, the solenoid 36 will remain energized until it raises the lever 24, but the raising of the lever is accomplished quickly, and with a slow moving train said lever may be raised while the armature 5a or 54 is passing; a track magnet, while with a fast moving train the armature 54-. or 54;" may have moved a short distance beyond the track magnet before the lever is completely raised, such variation, however, not oeing suihcient to affect or interfere with the working of the apparatus, due to the latitude of distance control as hereinafter pointed out.

True/ c circuits and control elements Disposed on the track at suitable spaced int-rvi..ls'are the electro-ma nets 68 and 69 which are arranged in p; rs spaced apart usvcrsely. These electro-magnets are is d for crcatin magnetic flu t the spaced points alon g the track for the attraction. of the respective arn'iatures 54 and 54, although said electro-magnets may be substituted by other electrically operated or energized contr elements or devices. Such clectro-mage. nets or control elements are spaced apart a ro-niagnet say every thousand feet or low thousand feet, as may be decided when making; the installation of the aptlaid magnets when c ergized proietic fields in the paths of the armaturos 5t and fi lwhich are responsive to the magm ic flux, so that the track control ele' "s cing energized will enable responses to be received by the vehicle equipment intervals while the locomotive is moving along the track. The blocks may be of different lengths and the longer blocks would naturally include a larger number of electro-inagnets or control elements. As shown, the track is divi =e 1l into the blocks A, B and C, and the rails ted between the blocks. liln elecet 70 has its terminals connected to the opposite rails in each block, and a battery or other source of electrical current '71 is also connected to the opposite rails in each block, which elcctro-inagnets and batteries may be use of the signal circuits as well known. l i hen any block is occupied, the wheels and axles of vehicle therein will connect the rails for tie respective blocks A, B and G. electro-magrnet 70 controls switches 72 and 78, the eiectro-magnet 70 controls switches 74 and 75, and the electro-magnet 70 controls the switches 7 6 and 77, which are held raised when said electro-magnets are enere'ized.

The track circuits for each block are the same, and only the circuits for the block A will be described in detail, the circuits of the nals of the conductors at the entrance end of i the block (the dir ction of travel bemgtoward the right as shown) are connected to the contact 82. When. the block A is unoccupied, so that the electro-magnet 70 can be energized, the switch 73 is raised from the contacts 82 and 83, thereby disconnecting the magnets 68' and 69 from the source of energy, so that such energy is not consumed or wasted. How-' ever, when the locomotive enters the block A, and the blocks B and C are unoccupied, so

that the electronnagnets 70 and 70" are en-.

ergized to raise the switches 7 i75 and 767 7, the circuits of the magnets 68 and 69 of the block A are com )leted. One circuit includes the supply wire 8, contact 88, switch 73 (which has been dropped by the deenergization of the electro-magnet 70 with the block A occupied), contact 82, conductor 80, including the coils or windings of the electromagnets 68, contact 84, switch 74 in raised position, and conductor leading to the feed wire 7 9. The other circuit includes the wire 7 8, contact 83, switch 73, contact 82, conductor 81, contact 86, switch! 5 in raised position, contact 87, conductor 89, cont-act 90, switch 76 in raised position, and conductor 91 connected to the feed wire 79. The circuit of electro-magnet 68 therefore includes the switch controlled by the electro-inagnet 70' of the next block ahead (block B) and the switch 76 of the second block ahead (block C), while the circuit of the magnets 69 includes the switch 7 4 controlled by the electroma net 70 of the first block ahead without inc uding a switch controlled by the electromagnet 7 0" of the block C. Consequently, if the blocks B and C are unoccupied, and the block A is occupied, the circuits of the magnets 68' and 69 in the block A will be closed ind such magnets therefore energized. If the block C is occupied, so that the electromagnet 70 is deenergized, the switches 76 and 77 are released, and this-will disconnect the conductors 89 and 91, thereby opening the isircuit of the magnets 68 in block A, so that such magnets are deenergized while the magnets 69 in such block remain energized. This produces a caution track condition with a vehicle in the second block ahead. Should The block B be occupied, the electro-magnet 70' being deenergized would release the switches 74 and 75, thereby opening the circuits of all of the magnets 68 and 69 in the block A and producing a danger traffic condition, there being a vehicle in the next block ahead. Therefore, with all of the track magnets energized, clear traffic conditions exist, the track being unoccupied sufliciently far ahead to permit of unrestricted speed; when the magnets 68 only are energized with the magnets 69 deenergized, a caution traflic condition exists, with a block occupied ahead requiring the vehicle following to reduce its speed; and with all of the magnets deenergized a danger condition exists. Danger conditions will also exist if the circuits or current fail. Under clear or caution conditions, however, the current will not flow through the track magnets unless the particular block is occupied, thereby effecting a saving in electrical energy by not requiring energy for the track magnets excepting for the occupied blocks, and then only if clear or caution trafiic conditions exist. The trackside circuits constitute part of the usual wayside signal circuits, and it will be apparent that the track equipment may be used independently of or in connection with the wayside signal circuits.

The track magnets are arranged in two longitudinal series side by side in pairs, with two magnets at each reset point of the track, and the magnets 68' and armature 54 are for caution conditions, while the magnets 69 and armature 54 are for clear conditions, danger conditions existing when all track magnets are deenergized. With this arrangement caution or danger conditions can be established immediately when passing a reset point of the track with the track magnets deenergized accordingly, and the arrangement also provides for the immediate clearing of the vehicle equipment when passing a single reset point of the track with the trackmagnetsenergizedaccordingly. In this way, either clear, caution or danger conditions may be established at any control point.

Operation Theapparatus,intheembodiment as shown, is operable for establishing clear, caution and danger conditions in the vehicle equipment, for the control of the locomotive accordingly, although other conditions may be provided for. The establishment of the several different conditions will be described separately.

Clear conditions lVhen the blocks B and C are unoccupied then clear conditions exist in the block A, and when the locomotive enters such block A, the electro-magnet 7 0 being deenergized and the switch 7 3 dropped will close the circuits of the electro-magnets 68 and 69 in such. block for resetting the run-down device at each resetting point of the track where the magnets are located.

Supposing the armatures 54 and 5st to be approaching the first magnets 68 and 69, respectively, with the lever 24 moving downwardly, the armatures passing over the energized magnets will move the switches 55 and 55 against the contacts 56 and 56, thereby energizing the solenoid 36 and returning the lever 24: to starting position, as hereinbefore described. Now, as the armatures 54 and 54 move with the vehicle away from the first pair of magnets toward the second pair of magnets 68 and 69, the lever 2-1 moves downwardly proportionately to the distance travelled. The distance D represents substantially the distance the vehicle must move before the lever 24: has moved downwardly sutficiently to remove the switch 17 from the strip 1.8, such distance being greater than the distance between the pairs of electro-magnets on the track, there being a suflicient latitude to assure of a resetting of the run-down device occurring before the retarding condition will occur.

Now, with the vehicle travelling from the first pair of magnets on the track to the second pair of magnets, the lever 2% is moving downwardly, and when the armaturcs 54, and 54 pass the second pair of track magnets the switches 55 and 55 are closed momentarily, thereby again energizing the solenoid 36 and returning the lever 24 to starting position. This same action is repeated as the vehicle passes the successive pairs of track magnets, and as long as the successive track magnets are energized, the rundown device is repeatedly reset to keep the normal running circuit closed, unless there is a failure in any of the circuits or other portions of the apparatus, failures being on the side of safety. If the switch 12 is in released position, away from the contact 13, the closing of the switch 55 when passing an energized electromagnet 69 will restore said switch 12, the restoring circuit including the generator 11, electromagnet 57, switch 58, contact 39, conductor 97, electromagnet 103, conductor 98, switch blade 99, contact 56,

. switch 55 conductor 61 contact stria 62 switch 63, contact strip 64 and conductor 65. The electromagnet 103 being energized will restore the switch 12. During clear conditions, therefore, with all of the track magnets energized, the run-down device repeatedthat under clear conditions the magnets 69 may be energized and the magnets 68 deenerglzed.

O'antion conditions With the block C occupied, caution conditions exist in the block A, inasmuch as the switch 76 being released to move away from the contact 90, will open the circuit of the magnets 68 in the block A, so that the mag- 68 are deenergized while the magnets 59 are energized for caution conditions.

Supposing the vehicle to be entering the block A with the armatures 54" and 54 approaching the first pa r of track magnets and the lever 24 moving downwardly, when the rmatures pass over the track magnets, the armature 54 will remain in normal position, because the magnets 69 are deenergized, while the armature 54 will be attracted by the magnet 68. The switch 55 being moved against the contact 56 will energize the solenoid 86 and reset the lever 24, to prevent the switch 17 moving away from the strip 18, but the armature or switch 54 being moved away I from the contacts 16", will break the normal running circuit between the conductors 1D and 95, thereby deenergizing the magnet 14, and the magnet 103 which is in the circuit of the contact 56 and switch 55 remains de 7 energized because the armature 54' has not moved. Therefore, the normal running circuit being broken will let the switch 12 fall down onto the contact 42. A caution conchtion is therefore established at once, including the caution speed control circuit. Such 21, strip 20 and conductor 22. If the vehicle is travelling above the maximum caution speed, with the switch 45 above the strip 44, the caution speed control circuit is opened and the magnet 10 deener'- gized to retard the movement of the train, and when the switch 45 engages the strip 44, the circuit is closed to energize the magnet 10 so as to permit the vehicle to proceed, but the speed is limited to that allowed under caution control. Such caution control will continue as long as the switch 12 is down against the contact 42, but a danger condition is not established providing the magnets 68' are energized. Before the lever 24 has run down completely, it is reset, therefore, by the response of the armature 54" to the electro-magnets 68, thereby preventing a danger condition from being established.

Danger conditions When the block B is occupied, so that the electro-magnet 70 is deenergized, the switches 74 and 7 5 moving downwardly will open the circuits of all of the magnets 68' and 69' in the block A, thereby producing an indication of a dangerous traflic condition. The caution and danger conditions in the vehicle equipment are obtained simultaneously in passing a pair of deenergized track magnets, thereby enforcing danger conditions at once. Thus, supposing the locomotive to be approaching the first track magnets which are deenergized, the armatures 54 and 54 failing to respond will let the run-down device go to danger position, so that the lever 24 moves completely down, thereby removing the switch 17 from the strip 18. This opens the circuit of the magnet 10 and compels the locomotive to come to a stop. When the locomotive has come to a stop, so that the switch 45 is brought against the contact 46, and the engineer closes the switch 51 with the member against the contact 35, the magnet 10 will be reenergized so that the train can proceed. The circuit for energizing the magnet 10 in cludes the generator 11, magnet 10, switch 12, contact 42, conductor 43, contact strip 44, switch 45, contact 46, contact 47, switch 48, magnet 49, conductor 50, switch 51, conductor 19, switch 21, contact 35, member 34 in closed position against contact 35, and conductor 22. The lever 24 not being resset remains in its lowermost position while the train is running under danger control. The magnet 10 being reenergized willpermit the vehicle to proceed, and the magnet 49 being simultaneously energized will raise the switch 48 away from the contact 47 against the contact 53 which is connected to the danger speed control strip 52 engaged by the strip 45. This will change the control, when a stop is made, from the stop contact 46 to the danger speed control strip 52. The vehicle can then increase its speed, but not above the speed limit for danger control, because if such speed is exceeded, the switch 45 being removed from the strip 52 will open the circuit of the magnet 10. Also the magnet 49 being deenergized will release the switch 18 so that said switch will swing away from the contact 53 back against the contact 47, again compelling the vehicle to come to a stop before it can proceed. It is also necessary, when proceeding under danger control, for the engineer to hold the switch 51 closed, thereby assuring that he is alert for making a stop immediately whenever necessary, even though travelling at a slow speed. These conditions will prevail as long as the track magnets are deenergized and the lever 24 remains in its lowermost position, there being nothing to reset the run-down device.

It will therefore be apparent from the foregoing description that whenever the armatures 54 and 54; pass a pair of energized track magnets, or an energized track magnet 69', clear conditions are established or maintained in the vehicle equipment; when the armatures pass a pair of track magnets with the magnet 68 energized and the magnet 69' deenergized, caution conditions are established in the vehicle apparatus, and such conditions will be continued while passing the Crack magnets with the magnets 68 energized and the magnets 69' deenergized; and when passing a pair of track magnets with both of them deenergized a danger condition is established. Such conditions are estabished at any point of the track, to obtain almost completely continuous control. The speed restrictions for caution conditions permits of higher speed than under danger control, to facilitate traiiic, inasmuch as the most stringent speed restriction is not necessary under caution conditions as it is under danger conditions. Furthermore, the vehicle equipment can be restored, whenever passing an energized track magnet 68 from a danger ;o a caution condition, and can be restored to clear conditions whenever passing an en ergized track magnet 69, as will presently appear.

Gleaming operation Supposing the locomotive to be travelling under danger control with the lever 24; completely down and the switch 48 against the contact 53, as hereinbefore described, whenever the armature 54 passes an energized track magnet 68, the track must either be clear or under caution conditions ahead. Therefore, whenever the armature 54: passes an energized track magnet 68, to close the .;witch the solenoid 36 is energized to return the lever 24 to initial or starting position, and as soon as the switch 17 is returned to the strip 18, the danger control contact 4-6 and strip 52 are removed from the circuit of the magnet 10, and a caution condition is tor 19, switch 21, strip 20 and conductor 22.

A caution condition is thus obtained when travelling under danger control past an energized magnet 68. If the magnets 69 are deenergized the vehicle must proceed under caution control, as hereinbetore described,

the lever 24 being returned to starting position when passing each magnet 68 in energized condition, thereby keeping the switch 17 on the strip 18.

When proceeding under caution control, either by a stepping down from clear to cau-- tion, or by stepping up from danger to caution, the vehicle equipment may be cleared automatically, but not unless the clear magnets 69 are energized to assure of the track being clear.

lVhen proceeding under either caution or danger speed control, and the armature 54: moves over an energized magnet 69, the switch 55 is closed against the contact 56 thereby energizing the solenoid 36 and magnet 108, so as to raise the lever Ql and switch 12. This restores the normal running circuit of the vehicle.

Summing up the operation briefly it Will be observed that when the track magnets 69 are energized, the locomotive can proceed without speed restriction; when the magnets 69 are deenergized with the magnets 68 remaining energized, a caution condition is established when the vehicle passes a pair of track magnets, and such condition will be maintained with the magnets 68 energized and the magnets 69 deenergized; when a pair of track magnets are passed when both are deenergized the vehicle equipment will go to danger condition, enforcing a slower speed than when under caution conditions; when proceeding under danger control and an energized magnet 69' is passed, the vehicle equipment will step up to caution control; and when proceeding under either danger or caution speed control and a pair of magnets 68 and 69 are passed with both of them energized, or only the magnet 69 energized, the vehicle equipment will he stepped up to a clear condition. Such conditions can be established while the locomotive is moving in the block, in order to provide almost continuous control, for purposes of safety in retarding or stopping the locomotive, even when it has entered a block, when a caution or danger condition presents itself, and for the further purpose of facilitating traffic by removing the speed restriction, even before reaching the end of the block, when caution or clear track conditions exist. Although the present apparatus is not, strictly speaking, continuous control it has the advantages thereof to a marked degree, without the disadvantage of using a sensitive detector for detecting alternating or other electrical current flowing in the rails, or the like. The apparatus, although somewhat intermittent in character, is not like the prevailing or known types of intermittent or block entrance initiated control apparati in which the several conditions can only be obtained at control stations. The present apparatus is therefore a compromise between the present known continuous control and the intermittent or block entrance initiated control, having advantages of both and eliminating disadvantages of each of them. By using the inductive elen'ients on the track and vehicle, contactdevices are eliminated, although they may be used, so far as the control of the vehicle equipment is concerned, the switches and 55 or their circuits being readily closed by different mediums available in the prior art. The inductive means for control of the vehicle equipment from the track, however, is preferable, because 01 the elimination of contact devices which are subject to jars and shocks, breaking off and other accidents, as well as constituting objectionable obstructions, while inductive devices between the track and vehicle can have clearances of several inches, without physical contact, and may be removed sufliciently from the line of clearance between the track and vehicle so as not to constitute objectionable obstructions, either on the track or on the vehicle.

Reversing switch hen the locomotive is turned around so as to travel with its other end forward, the

connections with the armatures 54 and 54 and their switches are reversed. The reversing switch blades 92, 94, 96 and 99 are connected to the rover ing lever 12-3 of the locomotive, and when such lever is moved to reverse the locomotive, the blades 92 and 94 connect the conductors 15 and 95 with the contacts 16 engaged by the armature 54:, and the blades 96 and 99 will connect the conductors and 98 with the contacts 56 and 56", respectively, so that the armature 54' now controls the circuit of the magnet 14 while the switch 55 controls the circuit of the magnet 103.

Having thus described the invention, what is claimed as new is 1. Vehicle cont-rolling apparatus comprising in combination witlia traclr divided into blocks; two sets of control elements in each block arranged in different longitudinal lines and each including a series of control elements located at intervals along the track in the block, means controlling said control elements of each block and controlled by traiiic conditions for rendering at least one set of control elements operative under clear conditions, the other set operative and the first named set inoperative for caution conditions,

and both sets inoperative for danger conditions; the control elements of one set being arranged adjacent to the control. elements or the other set throughout each block; a vehiclecarried run-down device operable whenever the vehicle is in motion for obtaining danger vehicle conditions when the vehicle has travelled a distance greater than the distance between the control elements of one set; and vehicle-carried means having separate resp i-iVc elements in said longitudinal lines controlled by said control elements and corn trcliing said run-down device and operable when responding to control elements of the lirstnamcd set to reset said run-down device and. maintain clear vehicle conditions, and operable when responding only to the control. elements of the secondnamed set, with the lirstnained set of elements inoperative, to reset said ruirdown device and maintain cau tion vehicle conditions.

ehicle controlling apparatus comprisin tombination with a track divided into blocks; two sets of control elements in each blorlr arranged in different longitudinal lines and each including a series of control elements located at intervals along the track in the block, means controlling said control elements of each block and controlled by trafllC conditions for rendering at least one set oi control elements operative under clear conditions, the other set operative and the ,tnamed set inoperative for caution conditions, and both sets inoperative for danger conditions; the control elements of one set being arranged adjacent to the control eleof the other set throughout each block; vehicle-carried run-down means operable whenever the vehicle is in motion for obtaining danger vehicle conditions when the vehicle has travelled a distance greater than the di tance between the (ontrol elements of one set; and 'ehicle carried means including a responsive element in one of said lines controlled by the control elements of the first- .named set and a second responsive element in the other of said lines controlled by the control elements of the secondnamed set, said responsive elements controlling said rundown means for resetting said run-down device when either responsive element responds to an operative control element, and means for producing caution conditions when the secondnan er responsive element is affected by a control element of: the secondnamed set without the firstna-med responsive element being eilected by a control element of the. firstnamed set.

3. Vehicle controlling apparatus according to the previous claim wherein the lastnamed vehicle-carried means has provisions for changing from danger to caution or clear vehicle conditions or from caution to clear vehicle conditions depending on the responsive elements passing the control elements with either set operative.

4. Vehicle controlling apparatus including a run-down device on the vehicle operable Whenever the vehicle is in motion for obtaining an ultimate vehicle condition pairs of adjacent control elements located at intervals along the track in different longitudinal lines, separate receiving elements on the vehicle in said lines cooperable with said control elements, means controlled by the receiving elements when passing a pair of said control elements with either control element energized for resetting the run-down device to maintain one of two other vehicle conditions, and means controlling said control elements and arranged for rendering at least one control element of each pair of operative for one track condition and the other control elements operative with the firstnained control elements inoperative for another track condition.

In testimony whereof I hereunto afiix my signature.

MONROE E. MILLER. 

